JPH09180401A - Magnetic tape cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the forming accuracy and stock property of an upper reel in a magnetic tape cartridge where two reels are arranged and overlapped in two stages. SOLUTION: Two reels including a lower reel 4 are overlapped in two stages and are housed in a casing 2 and a magnetic tape cartridge 1 has an upper reel 3 where a boss 34 through a center hole 41a of a hub 41 of the lower reel 4 protrudes on the lower surface of an own hub 31. The upper reel 3 is connected in one piece with the hub 31 due to the engagement of an engagement projecting part 31b and an engagement recessed part 34b after the boss 34 is formed separately from the hub 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape cartridge, for example, a magnetic tape cartridge suitable for use as an external memory of a large-scale general-purpose computer. The present invention relates to a magnetic tape cartridge.

[0002]

2. Description of the Related Art Generally, a magnetic tape is used as an external memory of a large general-purpose computer. The magnetic tape in this case is wound around a single reel and is housed in a substantially square box-shaped casing so that it can be handled as a cartridge. Then, when the cartridge is loaded on the hard side of the computer, one end of the magnetic tape is pulled out from the cartridge, the magnetic tape is loaded along the tape transport path equipped with the recording head and the reproducing head, and the reel in the hardware is loaded. Equipped with a magnetic tape transport mechanism for winding.

However, in this case, since it is necessary to provide a reel for winding on the hard side, there is a problem that the structure on the hard side becomes complicated. Therefore, a magnetic tape cartridge in which two reels are housed in a casing has been proposed. However, in this case, when two reels are arranged side by side in the casing and each reel is rotated about two parallel axes, as in a VHS video cassette, for example, the casing is more than the conventional magnetic tape cartridge. Is increased in width, resulting in an increase in overall size, which is not preferable.

Therefore, a magnetic tape cartridge having a structure in which two reels are coaxially arranged in a two-stage stack and are housed in a substantially square casing slightly larger than the reel diameter is conceivable. In the case of the reel two-stage stacking type magnetic tape cartridge, although the thickness of the casing is slightly increased, the width of the casing can be made the same as that of the conventional one.

[0005]

By the way, as described above, when two reels are stacked in two stages, the upper reel and the lower reel must be driven separately in a state where they are mounted in hardware. Therefore, by inserting a boss protruding from the lower surface of the hub of the upper reel into the center hole of the hub of the lower reel, the driven portions of both reels, that is, the hub of the lower reel, are inserted into the mounting holes provided on the lower surface of the casing. It is possible to concentrically expose the lower surface of the and the lower surface of the boss of the upper reel. This makes it possible to easily connect the driven parts of the reels to the coaxial drive shafts (inner shaft, outer shaft) on the hardware side when mounted on the hardware.

However, if the boss is integrally formed on the hub of the upper reel, it is difficult to secure high molding accuracy due to the complexity of the shape (for example, abrupt change of the wall thickness), and the productivity is lowered. There's a problem. Since precision is especially required around the hub, the factors that reduce precision must be eliminated as much as possible. In addition, if the molded product has a protruding portion such as a boss, the stockability at the time of accumulating and storing the components is poor, which may cause unnecessary damage.

In consideration of the above circumstances, the present invention is applied to a magnetic tape cartridge of a type in which two reels are coaxially arranged in a two-stage stack. An object of the present invention is to provide a magnetic tape cartridge provided with a reel that facilitates storage.

[0008]

SUMMARY OF THE INVENTION The above object of the present invention is to accommodate two reels in the casing in the thickness direction of the reel, and to penetrate one end of the hub of one reel through the center hole of the hub of the other reel. A magnetic tape cartridge comprising a two-stage stacking type reel having a boss protruding from the hub, wherein one of the reels has the boss molded separately from the hub,
This is achieved by a magnetic tape cartridge characterized in that it is integrally connected to the hub. In this case, as a preferred embodiment, the boss and the hub of the reel may be joined by fitting the engaging protrusion and the engaging recess, or the boss and the hub may be joined by welding.

[0009]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of a reel of a magnetic tape cartridge according to the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view of a main part of a magnetic tape cartridge in which the reel according to the present invention is incorporated as an upper reel.
FIG. 6 is an exploded cross-sectional view of an upper reel. 3 is an exploded perspective view of the magnetic tape cartridge of the present invention.

As shown in FIG. 3, the magnetic tape cartridge 1 of this embodiment has a square box type casing 2 made of synthetic resin or the like. The casing 2 is composed of a lower main body 2A and a cover 2B to cover the lower main body 2A, and is closed with the magnetic tape 5 and the reels 3 and 4 accommodated therein. A magnetic head on the hard side of the tape 5 (not shown)
Has an opening 6 with a shutter 7 for contacting with, and a circular mounting hole 8 on the lower surface for mounting to a drive unit on the hardware side.

In the casing 2, an upper reel 3 and a lower reel 4, which are each made of synthetic resin or the like, are coaxially housed in a two-stage stack. As shown in FIG. 1, the lower reel 4 has a hub 4 with a central hole 41a around which the magnetic tape 5 is wound.
1 and a disk-shaped upper flange 42 and lower disk-shaped flange 43 provided at both ends (upper end and lower end) in the axial direction of the hub 41. The upper flange 42 and the lower flange 43 are
The magnetic tapes 5 face each other in parallel with each other with a space slightly larger than the width of the magnetic tape 5. Here, for example, the lower flange 4
3 is formed integrally with the hub 41, the upper flange 42 is formed separately from the hub 41, and then on the upper end surface of the hub 41,
It is properly fixed by adhesion or fitting.

The upper reel 3 has a ring-shaped hub 31 around which the magnetic tape 5 is wound around its outer peripheral surface, and disk-shaped upper and lower flanges 32 and 32 respectively provided at both ends (upper end and lower end) in the axial direction of the hub 31. 33 and 33. Upper flange 3
2 and the lower flange 33 face each other in parallel with each other with the same interval as in the case of the lower reel 4. Here, the lower flange 33 is integrally formed with the hub 31, and the upper flange 32 is
Is molded separately from the hub 31, and is appropriately fixed to the upper end surface of the hub 31 by adhesion or fitting.

On the lower surface of the inner peripheral portion of the hub 31 of the upper reel 3, a cylindrical boss 34 which is inserted into the center hole 41a of the lower reel 4 is provided in a protruding manner. As shown in FIG. 2, the boss 34 is resin-molded separately from the hub 31 of the upper reel 3 and then integrally joined later. Therefore, the lower surface of the hub 31 of the upper reel 3 is formed into a substantially flat shape at the time of molding.

As a structure for connecting the hub 31 and the boss 34, first, at the center of the hub 31, a stepped center hole 31a having an upper small diameter portion and a lower large diameter portion is formed, and the stepped central hole is formed. An annular engagement recess 31b is formed around the inner circumference of the stepped portion 31a. On the other hand, the cylindrical boss 34
At the upper end of the thick-walled main body portion 34a, the thin-walled small cylinder 3 fitted to the inner periphery of the lower diameter small portion of the stepped center hole 31a on the hub 31 side.
4b is projected. The inner peripheral surface of the thin small cylinder 34b and the inner peripheral surface of the thick main body 34a are smoothly continuous,
The inner diameter is set equal to the inner diameter of the upper small diameter portion of the stepped center hole 31a of the hub 31. In addition, the thick body 3
Between the upper end surface 34c of 4a and the outer peripheral surface of the thin small cylinder 34b, a step portion that fits into the lower end peripheral edge of the stepped center hole 31a of the hub 31 is formed. In addition, an annular engaging projection 34d that snap-engages with the engaging recess 31b on the hub 31 side is formed on the outer periphery of the tip of the thin small cylinder 34b.

Then, the thin small cylinder 34b of the boss 34 is
By fitting into the stepped center hole 31a of the hub 31, the engagement concave portion 31b and the engagement convex portion 34d are engaged with each other, whereby the hub 31 and the boss 34 are integrally coupled. An adhesive is applied to the fitting surface as needed.

The upper reel 3 thus constructed is housed in the casing 2, and the upper reel 3 and the lower reel 4 are provided at the lower end of the hub 31 of the upper reel 3 in a two-tiered state. The cylindrical boss 34 has the central hole 41 of the lower reel 4.
a. As a result, the casing body 2A
Into the mounting hole 8 formed in the bottom wall of the upper reel 3
The lower end surface of the lower reel 4 and the lower surface of the inner peripheral portion of the hub 41 of the lower reel 4,
Each is individually rotatable and is exposed coaxially.

The boss 3 of the upper reel 3 exposed in the mounting hole 8
A ring-shaped engagement tooth 35 is formed on the lower end surface of the drive member 4 for rotating the upper reel 3 by a drive unit (not shown) in the hard disk. A metal ring 36 that is attracted to (not shown) is fixed by an adhesive or the like. Since the upper reel 3 is biased downward by the coil spring 23,
The engagement with the hard side can be performed relatively easily, and the metal ring 36 for attracting the magnetic force is not essential and can be omitted. On the lower end surface of the inner peripheral portion of the hub 41 of the lower reel 4, engagement teeth 45 for rotationally driving the lower reel 4 by a drive unit (not shown) in the hardware are formed in a ring shape. A metal ring 46, which is attracted to a magnet chuck (not shown) in the hardware, is fixed to the outer peripheral side with an adhesive or the like.

Further, as shown in FIG. 1, at the center of the casing 2, there is provided a cylindrical portion 21 extending downward from the lower surface of the upper wall of the cover 2B, and at the lower end of the cylindrical portion 21, a cylindrical portion is provided. A cap 22 biased downward by a coil spring 23 housed in 21 is covered. The cap 22 presses the receiving member 24 fixed to the center of the upper end of the upper reel 3 downward to urge the upper reel 3 downward, and at the same time, the upper reel 3 causes the lower reel 4 to move.
Is urged downward.

Further, on the upper surface of the bottom wall of the main body 2A of the casing 2, ring-shaped engaging teeth 28 which engage with the ring-shaped engaging teeth 48 formed on the lower surface of the hub 41 of the lower reel 4 are formed. On the upper surface of the hub 41 of No. 4, ring-shaped engaging teeth 47 that engage with the ring-shaped engaging teeth 37 formed on the lower surface of the hub 31 of the upper reel 3 are formed. These are for stopping the rotation of the reels 3 and 4 when the magnetic tape cartridge 1 is not mounted hard.

Further, in this magnetic tape cartridge 1, as shown in FIG. 3, both reels 3 and 4 wind up one end side and the other end side of one magnetic tape 5, respectively,
Since the magnetic tape 5 is run between the four reels, when the magnetic tape 5 is run from one reel 3, 4 in a two-stage stack to the other reel 4, 3, it is pulled out from one reel 3, 4. Tape guides 11, 12, 13, and 14 for obliquely guiding the magnetic tape 5 toward the other reels 4 and 3 are provided.

In this case, the magnetic tape 5 is the casing 2
The rear end side (the side opposite to the side with the opening 6 with the shutter 7) is adapted to move in and out of the reels 3 and 4, and the inside of the casing 2 is detoured as much as possible to make about one round (360 degrees round). The upper and lower reels 3, 4
The position of the height is changed with respect to. Therefore, the inclination angle in the running direction of the magnetic tape 5 for changing the position of the height is set to be gentle as much as the transition section from the one reel 3, 4 to the other reel 4, 3 can be made longer. The magnetic tape 5 obliquely passes through the opening 6 with the shutter 7 in the section that moves between the reels 3 and 4 as described above,
This portion comes into contact with the hard magnetic head.

Next, the operation will be briefly described. When this magnetic tape cartridge 1 is loaded into hardware, the lower end surface of the hub 41 of the lower reel 4 and the boss 34 of the upper reel 3 are respectively attached to the upper ends of the outer and inner shafts of the hard drive, that is, the hard drive. The lower end surfaces of the reels engage with each other, and the reels 3 and 4 are lifted to the fixed positions at the time of mounting so that they can be rotated. In this state, the drive mechanism on the hardware side drives the upper and lower reels 3 and 4 to rotate, so that the magnetic tape 5 is run from one reel 3, 4 to the other reel 4, 3.

In this magnetic tape cartridge 1, the boss 34 of the upper reel 3 is molded separately from the hub 31, and then
It is joined by fitting the hub 31 later. Therefore, the shapes of the hub 31 and the boss 34, which are required to have high molding accuracy, can be simplified, and the molding accuracy can be improved for each. In addition, by molding the boss 34, which is the protruding portion, separately, it is possible to make the shape of the upper reel 3 a flat shape at the time of molding, and as a result, good stockability during accumulation and storage. The potential for unnecessary damage can also be reduced. In addition, since the boss 34 is coupled to the hub 31 by fitting the engaging concave portion 31b and the engaging convex portion 34d, the both can be integrated by a simple operation.

The engaging recess 31b and the engaging protrusion 34d may not be formed in a continuous annular shape as described above, but may be formed intermittently in the circumferential direction. In that case, with the thin small cylinder 34b of the boss 34 fitted in the stepped center hole 31a of the hub 31, the boss 34 is rotated in the circumferential direction, whereby the engaging recess 31
The engagement convex portion 34d can be fitted to the b, and the hub 31 and the boss 34 can be prevented from rotating in this state. Therefore, the use of the adhesive can be omitted.

FIG. 4 is a sectional view showing a magnetic tape cartridge 1B incorporating an upper reel 3B as a second embodiment of the present invention, and FIG. 5 is an exploded sectional view of the upper reel 3B.
Since the structure of the magnetic tape cartridge 1B itself is exactly the same as that of the above-mentioned example, the same reference numerals are given in the drawings and the description thereof is omitted. Only the upper reel 3B will be described in detail focusing on the difference.

In the upper reel 3B, the hub 31 and the boss 3 are
The engaging concave portion 31b and the engaging convex portion 34d for coupling with 4
(See FIG. 2) is omitted, and instead, the boss 34 and the hub 31 are joined by, for example, ultrasonic welding. In FIG. 4, the position indicated by P is the welded portion. The other configuration is almost the same as the example of FIG.

Before welding, a welding protrusion Pa is provided on the upper end surface 34c of the thick body 34 of the boss 34 in advance. Then, the thin small cylinder 34b of the boss 34 is inserted into the stepped center hole 31a of the hub 31, and the welding protrusion Pa is pressed against the lower end surface of the hub 31 while welding is performed by an ultrasonic welding machine. As a result, the welding protrusion Pa portion is melted and the hub 3
1 and the boss 34 can be integrally connected. At this time, the fitting height of the boss 34 can be determined by the tip of the thin small cylinder 34b hitting the stepped portion of the stepped center hole 31a, and the assembling accuracy can be kept constant.

The upper reel 3B also has a boss 34 and a hub 31.
After molding it into a separate body, I decided to join it later,
There are similar advantages as above. Further, particularly in the case of this reel 3, since the boss 34 is joined to the hub 31 by welding, the integrity is enhanced, and the engaging convex portion and the engaging concave portion for joining are not required, and the shapes of the boss 34 and the hub 31 are not required. Becomes simple.

Of course, a coupling structure other than the above examples may be adopted to couple the boss 34 and the hub 31. Also in the embodiment shown in FIGS. 4 and 5, the metal ring 36
Can be omitted.

[0030]

As described above, in the reel for the magnetic tape cartridge according to the present invention, the boss and the hub are separately molded and then joined together. Therefore, high molding precision is required. The shapes of the hub and the boss to be formed can be simplified and can be molded accurately. Also,
By separately molding the boss that becomes the protruding portion, the shape of the reel can be made flat at the time of molding.
Therefore, the stockability during accumulation and storage can be improved, and the possibility of unnecessary damage can be reduced. Also, especially when the boss and the hub are connected by fitting the engaging concave portion and the engaging convex portion, it is possible to integrate them by a simple work, and when they are joined by welding, the simple shape provides the integrity. Can be strengthened.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a magnetic tape cartridge incorporating a reel according to an embodiment of the present invention.

FIG. 2 is an exploded sectional view of the upper reel of FIG.

FIG. 3 is an exploded perspective view of the magnetic tape cartridge.

FIG. 4 is a cross-sectional view of a magnetic tape cartridge incorporating a reel of another embodiment of the present invention.

5 is an exploded cross-sectional view of the upper reel of FIG.

[Explanation of symbols]

 1, 1B Magnetic tape cartridge 2 Casing 3, 3B Upper reel 31 Hub 31b Engagement concave portion 34 Boss 34d Engagement convex portion 4 Lower reel P Welding portion

Claims (3)

[Claims] 1. A two-stage stack type in which two tiers are accommodated in a casing in a two-tier stack in the thickness direction of the reel, and a boss penetrating through a center hole of the hub of the other reel is provided on one end side of the hub of the other reel. A magnetic tape cartridge comprising the reel of claim 1, wherein the one reel is formed by molding the boss separately from the hub and then integrally coupled with the hub. 2. The magnetic tape cartridge according to claim 1, wherein the boss and the hub of the reel are coupled by fitting an engaging convex portion and an engaging concave portion. 3. The boss of the reel and the hub are joined together by welding.
The magnetic tape cartridge described.